In Gilstrap v. State, 261 Ga. 798, 799 (2) (410 S.E.2d 423) (1991)., the trial court permitted the State to introduce evidence of nine similar transactions before it had offered any evidence concerning the charges in the indictment on trial. The trial court has discretion as to the order of admission of evidence, but that discretion is not unlimited. Gilstrap concluded that the procedure followed in the trial court raised a substantial possibility that the jury could have settled upon the guilt of the defendant based solely upon evidence of a large number of similar transactions before hearing a single witness testify as to the indicted offenses. Gilstrap, however, expressly declined to determine the limits of the trial court's discretion as to the order of the admission of evidence.